This disclosure relates to medical devices used to electrically stimulate the digestive system and more particularly electrical stimulation to influence pancreatic secretions.
The medical device industry produces a wide variety of electronic and mechanical devices for treating patient medical conditions. Depending upon medical condition, medical devices can be surgically implanted or connected externally to the patient receiving treatment. Clinicians use medical devices alone or in combination with drug therapies and surgery to treat patient medical conditions. For some medical conditions, medical devices provide the best, and sometimes the only, therapy to restore an individual to a more healthful condition and a fuller life. One medical condition that has been difficult to treat is the wide variety of pancreatic diseases.
The pancreas is an organ that has both exocrine and endocrine functions. Pancreatic exocrine functions include secreting enzymes and bicarbonate into the duodenum where they aid in digestion and absorption of nutrients. Pancreatic exocrine conditions include pancreatitis, inflammation of the pancreas, and cystic fibrosis, and pancreatic exocrine conditions can affect other gastrointestinal tract conditions such as nausea, vomiting, malabsorption syndrome, and pain. In addition to exocrine functions, the pancreas also performs endocrine functions. Pancreatic endocrine tissue is made up of pancreatic islets that produce hormones that control the metabolic functions of other organs. Pancreatic endocrine conditions include diabetes mellitus and pancreatitis.
Previous treatments for pancreatic exocrine and endocrine conditions using drugs and surgery do not satisfactorily treat some patient conditions. Drugs used to treat pancreatic conditions include insulin and pancreatic enzymes, and surgery used to treat pancreatic conditions includes pancreatic resection and transplant.
One previous treatment for pancreatic endocrine conditions involved applying an electrical stimulation signal to the vagus nerve to increase pancreatic endocrine secretions such as described in U.S. Pat. No. 5,231,988, “Treatment Of Endocrine Disorders By Nerve Stimulation” by Wernicke et al (Aug. 3, 1993). Vagal stimulation therapy is difficult to achieve and can adversely stimulate other organs. The electrodes used with vagal stimulation can also damage the vagal nerve by creating lesions.
Another previous treatment for pancreatic endocrine conditions involved applying an electrical stimulation signal directly to the pancreas such as described in U.S. Pat. No. 5,919,216, “System And Method For Enhancement Of Glucose Production By Stimulation Of Pancreatic Beta Cells” by Houben et al. (Jun. 6, 1999). Direct pancreatic stimulation therapy is not always effective in stimulating the entire pancreas.
For the foregoing reasons, there is a need for a neurostimulator configured to apply a stimulation signal to a patient's digestive system to influence pancreatic exocrine and endocrine secretions.